The study of cellular interactions is important to understand the development of a number of diseases. Devices for investigation of cellular interactions typically allow cells to grow on a horizontal monolayer over a sheet of collagen or other biocompatible gel. Such devices can be used, for example, with endothelial cells that eventually form blood vessels that grow downward. Adding drugs to these devices allow a qualitative assessment of the effect of the drug on the formation of blood vessels from the top of the device, where the blood vessels appear as holes in the gel. However, it is not possible to image the blood vessels from the side.
Thus, there is a need for improved devices that allow for the study of cellular interactions.